Thomas_redesign_ptI 8/10/09 9:20 AM Page 1 PEARSON’S Calculus Review, Single Variable Differentiation USEFUL DERIVATIVES DERIVATIVE The derivative of the function f (x) with respect to the variable x is the function f ¿ whose value at x is Limits LIMIT LAWS The limit of a rational power of a function is that power of the limit of the function, provided the latter is a real number. If L, M, c, and k are real numbers and lim f (x) = L and x: c 1. 7. lim g(x) = M, then x:c Sum Rule: lim ( f (x) + g(x)) = L + M 8. x: c USEFUL LIMITS 1. Product Rule: lim ( f (x) – g (x)) = L – M x: c 2. FINDING THE TANGENT TO THE CURVE y = f (x) AT (x0, y0) Quotient Rule: lim x:c Calculate f (x0) and f (x0 + h). 2. f (x0 + h) - f (x0) Calculate the slope f ¿(x0) = m = lim . h h :0 3. If the limit exists, the tangent line is y = y0 + m(x - x0). x: q q E - q(n(neven) odd) , lim x: ; q 1 = 0 xn 1. Constant Rule: If f (x) = c (c constant), then f ¿(x) = 0. 2. Power Rule: If r is a real number, 3. d Constant Multiple Rule: (c – f (x)) = c – f ¿(x) dx 4. Sum Rule: 5. Product Rule: (provided an, bm Z 0) 4. lim ( f (x)) x: c 1 + q (n even) lim n = E ; q (n odd) x: c ; (x - c) 6. Power Rule: If r and s are integers with no common factor r, s Z 0, then r/s For integers n, m > 0, 5. lim x: 0 sin x sin kx = k (k constant), lim x x = 1, x: 0 7. r/s = L cos x - 1 = 0 lim x x: 0 r/s provided that L is a real number. (If s is even, we assume that L 7 0.) d r x = rx r - 1 dx d [ f (x) ; g(x)] = f ¿(x) ; g¿(x) dx d [ f (x)g(x)] = f (x)g¿(x) + f ¿(x)g(x) dx g(x) f ¿(x) - f (x)g¿(x) d f (x) Quotient Rule: c d = dx g(x) [g(x)]2 dy du d Chain Rule: [ f (g(x))] = f ¿(g(x)) – g¿(x) = – dx du dx if y = f (u) and u = g(x) 2. d (cos x) = -sin x dx 4. d (cot x) = - csc2 x dx 5. d (sec x) = sec x tan x dx 6. d (csc x) = - csc x cot x dx 7. d x (e ) = e x dx 8. d x (a ) = (ln a)a x dx 10. 1 d (loga x) = dx x ln a 12. d -1 (cos-1 x) = dx 11 - x 2 14. -1 d (cot-1 x) = dx 1 + x2 1 d (ln x) = x dx 11. d 1 (sin-1 x) = dx 11 - x 2 13. 1 d (tan-1 x) = dx 1 + x2 DIFFERENTIATION RULES an x n + an - 1x n - 1 + % + a0 an lim = – lim x n - m bm x: ; q x: ; q bm x m + bm - 1x m - 1 + % + b0 f (x) L , M Z 0 = g(x) M d (tan x) = sec2 x dx 9. 1. x:c 3. 3. lim k = k, (k constant) x: ; q For an integer n > 0, lim xn = q , lim xn = The limit of a quotient of two functions is the quotient of their limits, provided the limit of the denominator is not zero. 6. lim k = k, x: c x: - q Constant Multiple Rule: lim (k – f (x)) = k – L The limit of a constant times a function is the constant times the limit of the function. 5. f (z) - f (x) z - x . z:x provided the limit exists; equivalently f ¿(x) = lim x: c The limit of a product of two function is the product of their limits. 4. If P(x) and Q(x) are polynomials and Q(c) Z 0, then the rational P(x) P(x) P(c) = function has lim . Q(x) Q(c) x: c Q(x) Difference Rule: lim ( f (x) - g(x)) = L - M The limit of the difference of two functions is the difference of their limits. 3. If P(x) = an x n + an - 1x n - 1 + % + a0 is a polynomial then lim P(x) = P(c) = ancn + an - 1cn - 1 + % + a0 . x: c The limit of the sum of two functions is the sum of their limits. 2. f (x + h) - f (x) , f ¿(x) = lim h h:0 d 1. (sin x) = cos x dx f (c) exists (c lies in the domain of f ) If f ¿(x) > 0 at each x H (a, b), then f is increasing on [a, b]. 2. lim f (x) exists ( f has a limit as x : c) If f ¿(x) < 0 at each x H (a, b), then f is decreasing on [a, b]. 3. x :c lim f (x) = f (c) x :c 9 0 0 0 0 2. 9 1 2. If f ¿(c) = 0 and f –(c) 7 0, then f has a local minimum at x = c. 3. If f ¿(c) = 0 and f –(c) = 0, then the test fails. The function f may have a local maximum, a local minimum, or neither. d -1 (csc - 1 x) = dx ƒ x ƒ 1x 2 - 1 If f is continuous on [a, b] then F(x) = La dF d f (t) dt = f (x), = dx dx La (2) 19. 20. d (coth x) = - csch2 x dx 21. d (sech x) = -sech x tanh x dx 22. d (csch x) = -csch x coth x dx INTEGRATION BY PARTS FORMULA 23. 1 d (sinh-1 x) = dx 11 + x 2 24. 1 d (cosh-1 x) = dx 1x 2 - 1 27. -1 d (sech - 1 x) = dx x11 - x 2 28. 1 d (coth - 1 x) = dx 1 - x2 3. 2. If f – < 0 on I, the graph of f over I is concave down. If f –(c) = 0 and the graph of f (x) changes concavity across c then f has an inflection point at c. if f ¿ changes from positive to negative at c, then f has a local maximum at c; more➤ 2 u dv = uv - du = u + C L 2. k du = ku + C (any number k) L 3. (du + dv) = du + dv L L L 4. L L un du = un+1 + C n + 1 (n Z -1) du u = ln ƒ u ƒ + C L 7. cos u du = sin u + C L 8. sec2 u du = tan u + C L 9. L L 17. cosh u du = sinh u + C L 18. u du = sin-1 Q a R + C 2 2 1a u L 19. 1 u du = a tan - 1 Q a R + C L a2 + u2 20. du 1 u = a sec-1 ` a ` + C L u1u2 - a2 21. u du = sinh-1 Q a R + C (a 7 0) L 1a2 + u2 22. u du = cosh-1 Q a R + C (u 7 a 7 0) 2 2 1u a L 23. sin u du = -cos u + C 6. 16. v du L 1. 10. 780321 608109 La cot u du = ln ƒ sin u ƒ + C eu du = eu + C L au 15. audu = + C, (a 7 0, a Z 1) ln a L USEFUL INTEGRATION FORMULAS INFLECTION POINT if f ¿ changes from negative to positive at c, then f has a local minimum at c; L 14. f (x) dx = F(b) - F(a). L SECOND DERIVATIVE TEST FOR CONCAVITY If f – > 0 on I, the graph of f over I is concave up. 13. = - ln ƒ csc u ƒ + C b 5. 1. tan u du = - ln ƒ cos u ƒ + C L = ln ƒ sec u ƒ + C If f is continuous at every point of [a, b] and F is any antiderivative of f on [a, b], then -1 d (csch - 1 x) = dx ƒ x ƒ 11 + x 2 if f ¿ does not change sign at c (that is, f ¿ is positive on both sides of c or negative on both sides), then f has no local extremum at c. 12. a … x … b. d (tanh x) = sech2 x dx 26. L x (1) d (cosh x) = sinh x dx 1 d (tanh - 1 x) = dx 1 - x2 f (t) dt is continuous on csc u cot u du = -csc u + C 11. [a, b] and differentiable on (a, b) and 18. 25. assuming that the limit on the right side exists. x d (sinh x) = cosh x dx Suppose that c is a critical point ( f ¿(c) = 0) of a continuous function f that is differentiable in some open interval containing c, except possibly at c itself. Moving across c from left to right, 1. If f ¿(c) = 0 and f –(c) < 0, then f has a local maximum at x = c. 17. FIRST DERIVATIVE TEST FOR LOCAL EXTREMA ISBN-13: 978-0-321-60810-9 ISBN-10: 0-321-60810-0 1. THE FUNDAMENTAL THEOREM OF CALCULUS Let y = f (x) be twice-differentiable on an interval I. (the limit equals the function value) Suppose that f (a) = g(a) = 0, that f and g are differentiable on an open interval I containing a, and that g¿(x) Z 0 on I if x Z a. Then f (x) f ¿(x) , = lim lim g(x) x:a x: a g¿(x) 16. Suppose that f is continuous on [a, b] and differentiable on (a, b). 1. Suppose f – is continuous on an open interval that contains x = c. 1 d (sec-1 x) = dx ƒ x ƒ 1x 2 - 1 15. FIRST DERIVATIVE TEST FOR MONOTONICITY A function f (x) is continuous at x = c if and only if the following three conditions hold: L’HÔPITAL’S RULE Integration Applications of Derivatives Continuity SECOND DERIVATIVE TEST FOR LOCAL EXTREMA L sinh u du = cosh u + C sin2 x dx = x sin 2x + C 2 4 24. x sin 2x cos2 x dx = + + C 2 4 L 25. sec u du = ln ƒ sec u + tan u ƒ + C L csc2 u du = -cot u + C 26. L sec u tan u du = sec u + C L 27. 3 csc u du = - ln ƒ csc u + cot u ƒ + C 1 1 sec3 x dx = sec x tan x + ln ƒ sec x + tan x ƒ + C 2 2 L Thomas_redesign_ptI 8/10/09 9:20 AM Page 2 Calculus Review, Single Variable Volume of Solid of Revolution b DISK V = La p[ f (x)]2 dx La 2pxf (x) dx USEFUL CONVERGENT SEQUENCES L = 2 [ f ¿(t)]2 + [ g¿(t)]2 dt Lc 21 + [ g¿(y)]2 dy 1. 2. where x = f (t), y = g(t) 3. Numerical Integration 4. b f (x) dx L 5. ¢x (y + 2y1 + 2y2 + % + 2yn - 1 + yn) 2 0 6. b - a n and yi = a + i¢x, y0 = a, yn = b where ¢x = lim n: q gan converges if there is a convergent series gcn with an … cn for all n 7 N, for some integer N. (b) gan diverges if there is a divergent series of nonnegative terms gdn with an Ú dn for all n 7 N, for some integer N. ln n n = 0 lim 1n = 1 n: q lim x n n: q 1. n: q 2. x lim a1 + n b = ex n: q xn n! 3. = 0 Let sn = a1 + a2 + an If lim = c 7 0, then gan and gbn both converge or both n : q bn diverge. an If lim = 0 and gbn converges, then gan converges. n : q bn an If lim = q and gbn diverges, then gan diverges. n : q bn THE RATIO TEST 3. xn e x = a , all x n = 0 n! 4. q (-1) x sin x = a , all x n = 0 (2n + 1)! 5. cos x = a 6. ln(1 + x) = a 7. tan - 1 x = a q q Á La f (x) dx L where ¢x = (a) ¢x (y + 4y1 + 2y2 + 4y3 + % + 2yn - 2 + 4yn - 1 + yn) 3 0 q n=0 8. (b) b - a n , n is even and yi = a + i¢x, y0 = a, yn = b x , -1 6 x … 1 (-1)n x 2n + 1 ,ƒxƒ … 1 2n + 1 m (Binomial Series) (1 + x)m = 1 + a a bx k, ƒ x ƒ 6 1 k=1 k n: q sn exists. a an converges if nlim :q n-1 n (-1) n n=1 m(m - 1) m m , where a b = m, a b = 1 2 2 q b n 2n (-1) x , all x n = 0 (2n)! q an Ú 0, lim + an. 2n + 1 q an+1 an = r, then gan converges if r 6 1, diverges if r 7 1, and the test is inconclusive if r = 1. SEQUENCE OF PARTIAL SUMS SIMPSON’S RULE 1 = a (-1)nx n, ƒ x ƒ 6 1 1 + x n=0 q = 1 (x 7 0) lim xn = 0 ( ƒ x ƒ 6 1) lim 2. Suppose that an 7 0 and bn 7 0 for all n Ú N (N an integer). 1 n: q 1 = a x n, ƒ x ƒ 6 1 1 - x n=0 n LIMIT COMPARISON TEST n n TRAPEZOID RULE La (a) d b La La LENGTH OF x = g (y) LENGTH OF PARAMETRIC CURVE L = 21 + [ f ¿(x)]2 dx q 1. Let gan be a series with no negative terms. 0! = 1, 1! = 1, 2! = 1 – 2, 3! = 1 – 2 – 3, n! = 1 – 2 – 3 – 4 % n b L = COMPARISON TEST FACTORIAL NOTATION LENGTH OF y = f (x) b SHELL V = USEFUL SERIES Infinite Sequences and Series m(m - 1) % (m - k + 1) m a b = ,k Ú 3 k k! n=1 q THE ROOT TEST sn does not exist. a an diverges if nlim :q an Ú 0, lim 1an = r, then gan converges if r 6 1, diverges if n n=1 n: q GEOMETRIC SERIES r 7 1, and the test is inconclusive if r = 1. FOURIER SERIES ALTERNATING SERIES TEST 1 1 f (x) dx, ak = p The Fourier Series for f (x) is a0 + a (ak cos kx + bk sin kx) where a0 = 2p L0 k=1 L0 an Ú 0, g(-1)n + 1an converges if an is monotone decreasing and lim an = 0. 1 bk = p ABSOLUTE CONVERGENCE TEST TESTS FOR CONVERGENCE OF INFINITE SERIES If g ƒ an ƒ converges, then gan converges. 1. The nth-Term Test: Unless an : 0, the series diverges. TAYLOR SERIES 2. Geometric series: gar n converges if ƒ r ƒ 6 1; otherwise it diverges. Let f be a function with derivatives of all orders throughout some interval containing a as an interior point. Then the Taylor Series generated by f at x = a is 3. p-series: g1n p converges if p 7 1; otherwise it diverges. 2p q q n-1 = a ar Polar Coordinates n=1 LENGTH OF POLAR CURVE EQUATIONS RELATING POLAR AND CARTESIAN COORDINATES x = r cos u 2 2 2 y = r sin u, x + y = r , u = tan -1 b y ax b L = SLOPE OF THE CURVE r f (u) La B r2 + a b A = n: q an fails to exist or is different from zero. a an diverges if nlim :q n=1 b 1 2 1 r du = [ f (u)]2du La 2 La 2 provided dx/du Z 0 at (r, u). AREA OF A SURFACE OF REVOLUTION OF A POLAR CURVE (ABOUT x-AXIS) CONCAVITY OF THE CURVE r f(u) THE nth-TERM TEST FOR DIVERGENCE THE INTEGRAL TEST Let {an} be a sequence of positive terms. Suppose that an = f (n), where f is a continuous, positive decreasing function for all x Ú N q (N a positive integer). Then the series g n = N an and the improper q integral 1N f (x) dx both converge or both diverge. q p-SERIES a k=0 q d dy b a ` du dx (r, u) d 2y dx2 = b S = La 2pr sin u r 2 + a B dr 2 b du du 1 a n p converges if p 7 1, diverges if p … 1. n=1 L0 f (x) sin k x dx, k = 1, 2, 3, Á f (k)(a) (x - a)k = f (a) + f ¿(a)(x - a) + k! 4. Series with nonnegative terms: Try the Integral Test, Ratio Test, or Root Test. Try comparing to a known series with the Comparison Test or the Limit Comparison Test. 5. Series with some negative terms: Does g ƒ an ƒ converge? If yes, so does gan since absolute convergence implies convergence. 6. Alternating series: gan converges if the series satisfies the conditions of the Alternating Series Test. If a = 0, we have a Maclaurin Series for f (x). dx Z 0 at (r, u). du more➤ 4 f (x) cos k x dx, 2p f –(a) f (n)(a) (x - a)n + % . (x - a)2 + % + 2! n! f ¿(u) cos u - f (u) sin u provided 2p q dr 2 b du du AREA OF REGION BETWEEN ORIGIN AND POLAR CURVE r = f(u) f ¿(u) sin u + f (u) cos u dy ` = dx (r, u) f ¿(u) cos u - f (u) sin u a , ƒ r ƒ 6 1, and diverges if ƒ r ƒ Ú 1. 1 - r 5 6